6.5L with idles with white smoke

[Chris]

I have a

[DieselDadd1]

There are many causes for a white smoke condition.First check for a restricted fuel return line.You may have a slight leak in the fuel suction or delivery line.A restricted fuel line or filter may cause this problem.The most likely cause however would be retarded injection pump timing.A continuing white smoke condition could indicate a loss of compression.Retarded timing and a plugged fuel return line though are the most likely causes in this case.Make sure the mark on the injection pump mating flange is perfectly aligned with the mark on the front cover.If the timing is retarded,you should see the mark on the pump to the left of the front cover mark.Perhaps the pump slipped or vibrated slightly loose causing this white smoke condition.With all of the diesel vibrating,it's quite possible for the pump to slip from it's marks due to loose fasteners.If your not comfortable in performing this procedure,then you should take it to the GM dealer for a complete inspection to determine the cause.Good luck.